System and method for conveying an assembly

ABSTRACT

Cleaning system ( 100 ) including a brush assembly ( 102 ) for cleaning solar panels ( 106 ). The brush assembly has at least one rotatable brush ( 403 ) having a rotational axis. The rotatable brush includes a plurality of sets of bristles ( 2004 ), each extending outwardly from a core ( 2008 ). A shaft ( 2005 ) extends through the core of the brush. The shaft is a telescoping shaft, which is configured to retract and expand to create an elongated brush assembly. An apparatus, system, and method for conveying an assembly along a track. A rail ( 401 ) includes a first planar side, a second planar side, and a third planar side. The first, second, and third planar sides are arranged to form at least two acute angles ranging between 50 degrees and 80 degrees. A carriage assembly ( 300 ) includes a drive wheel ( 301 ) and at least two rollers ( 302 ). The drive wheel is configured to contact the second planar side and is configured to translate the assembly along the rail. The two rollers are configured to contact the two other sides to maintain the carriage in contact with the rail.

CLAIM OF PRIORITY

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/014,227, filed Jun. 19, 2014; U.S. Provisional Patent ApplicationNo. 62/014,240, filed Jun. 19, 2014; U.S. Provisional Patent ApplicationNo. 62/014,248, filed Jun. 19, 2014; U.S. Provisional Patent ApplicationNo. 62/014,251, filed Jun. 19, 2014; U.S. Provisional Patent ApplicationNo. 62/014,253, filed Jun. 19, 2014; each of which is incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention is directed to a system and method for translatingan assembly along a track, such as a duster for dusting a photovoltaicarray.

BACKGROUND

The efficiency of a solar panel is measured by the ratio of the amountof sunlight it receives to the amount of electricity it generates. Aftera solar panel is installed, dust and other debris typically begin toaccumulate on the solar panel surfaces. Dust accumulated on a solarpanel reduces the number of photons reaching the photovoltaic elementsand thereby reduces the power the solar panel can generate during a unitof time. In other words, dust can significantly reduce the efficiency ofthe solar panel. Therefore, many systems include a solar panel cleaningsystem to improve the efficiency of solar panels.

Solar panel cleaners in the prior art can be categorized as manual andautomated types. Manual cleaners generally include manually operatedsweeping brushes, power washers, and powered brushes. Automated cleanersgenerally include buffer-style and rotating bristle-style devices. Priorrotating bristle-style cleaners generally use a system for translatingthe brush while the rotational axis of the brush is maintained in anorientation that is perpendicular to the direction of travel. In otherwords, the top and bottom of the brush sweep across the panel at an evenrate without one moving out ahead of the other. Complicated andmechanically inefficient systems are typically required to maintain therotating brush in a perpendicular orientation as it traverses the solarpanels. Changes in temperature and other variables can affect thefunctioning of such dusters.

Typically, most solar panel cleaning systems also use liquid cleaningsolutions or water for cleaning the solar panels. The moistened dust anddebris may become sticky and adhere to the surfaces of the solar panel,which can complicate the cleaning process. This is especially true inhot arid regions where solar panels are often found. A further problemwith using water in arid regions is in maintaining or supplying water atthe site of the solar array.

SUMMARY

In an aspect, a track system can include a rail and a carriage assembly.The rail can include a first planar side, a second planar side, and athird planar side. The first, second, and third planar sides can bearranged to form at least two acute angles. The carriage assembly caninclude a drive wheel and at least two roller sets. The drive wheel canbe configured to contact the first planar side and can be configured totranslate the carriage assembly along the rail. A first roller set ofthe at least two roller sets can be configured to contact the secondplanar side, and a second roller set of the at least two roller sets canbe configured to contact the third planar side.

In some embodiments, the track system can include a motor. The motor canbe configured to actuate the drive wheel and translate the carriageassembly. The drive wheel can be a load bearing roller. The carriageassembly can further include a pivot. The pivot can be configured topivot an attached component. In other embodiments, the drive wheel andthe at least two rollers can be configured to maintain the carriageassembly in contact with the rail.

In some embodiments, the rail can be formed of a cold rolled metal, forexample cold rolled steel, and/or the rail can be formed of an extrudedmetal, such extruded aluminum. The at least two rollers can comprise asilicon material, a metal material and/or a polymer material. The railcan be solid or hollow. The rail can include internal support structuresand hollow areas.

In another aspect, a conveying method can include the steps of providinga rail, providing a carriage assembly, and translating the carriageassembly along the rail. The rail can include a first planar side, asecond planar side, and a third planar side. The first, second, andthird planar sides can be arranged to form at least two acute angles.The carriage assembly can include a drive wheel and at least two rollersets. The drive wheel can be configured to contact the first planarside. A first roller set of the at least two roller sets can beconfigured to contact the second planar side. A second roller set of theat least two roller sets can be configured to contact the third planarside.

In some embodiments, the method can include actuating a motor, causingthe drive wheel to translate the carriage assembly. The drive wheel canbe a load bearing roller. The drive wheel and the at least two rollersmaintain the carriage assembly in contact with the rail.

In embodiments, the method can include pivoting an attached component,such as an assembly. The rail can be formed of a cold rolled metaland/or an extruded metal. The drive wheel and the at least two rollerscomprise a silicon material, a metal material, and/or a polymermaterial.

In an aspect, a cleaning apparatus can include a brush assembly, adrive, and a pivot. The brush assembly can include at least onerotatable brush having a rotational axis. The drive can be configured totranslate the brush assembly parallel to a track. The pivot can beconfigured to pivot the rotational axis in a plane parallel to the trackand the rotational axis.

In embodiments, the cleaning apparatus can include a trailing assemblyslidably attached to the brush assembly. The trailing assembly can beconfigured to translate along a second track. The pivot can beconfigured to allow the brush assembly to pivot in the plane to an anglethat is not perpendicular to the track. The angle can be between 30 deg.and 80 deg., between 40 deg. and 75 deg., between 50 deg. and 70 deg.,and/or between 55 deg. and 65 deg. The angle can be less than 60 deg.

In some embodiments, the drive wheel can include a drive motor. Thebrush assembly can include a brush motor configured to rotate the atleast one rotatable brush about the rotational axis. The at least onerotatable brush can include a sweeping member. In some embodiments, thesweeping member can have a bristle pattern parallel to the rotationalaxis. The sweeping member can comprise a polymer, a natural fiber,and/or metal bristles. The sweeping member can comprise a foam or spongymaterial.

In embodiments, the at least one rotatable brush can include a shaftextending along the rotational axis and a sweeping member coupled to theshaft and configured to be rotatable about the rotational axis. Thepivot can be configured to rotate the shaft clockwise and/orcounter-clockwise, as well as in a plane parallel to a solar panel orother element such as a window or mirror. The rotational axis is notperpendicular to the direction of the track while the cleaning apparatusis in an operational configuration.

In another aspect, a method of cleaning can include the steps ofproviding a brush assembly, pivoting the rotational axis of a rotatablebrush, and translating the brush assembly parallel to a track. The brushassembly can include at least one rotatable brush having a rotationalaxis. The plane defined by pivoting the rotational axis can be in aplane parallel to the track.

In some embodiments, the method can include providing a trailingassembly slidably attached to the brush assembly and translating thetrailing assembly along a second track. In other embodiments, the methodcan include pivoting the brush assembly in the plane to an angle that isnonperpendicular to the track. The angle can be between 30 deg. and 80deg., between 40 deg. and 75 deg., between 50 deg. and 70 deg., and/orbetween 55 deg. and 65 deg. The angle can be less than 60 deg.

In other embodiments, the method can include operating a brush motor torotate the at least one rotatable brush about the rotational axis. Theat least one rotatable brush can include a sweeping member having abristle pattern parallel to the rotational axis.

In an aspect, a photovoltaic array can include a rail and a solar panelmounted to the rail. The rail can include a first planar side, a secondplanar side, and a third planar side. The first, second, and thirdplanar sides can be arranged to form at least a first acute angle and asecond acute angle.

In some embodiments, the rail can be formed of a cold rolled metaland/or an extruded metal.

In some embodiments, the array can further include a carriage assemblyand a brush assembly. The carriage assembly can include a pivot, a drivewheel, and at least two roller sets. The brush assembly can include atleast one rotatable brush having a rotational axis. The brush assemblycan be pivotally attached to the carriage assembly.

In other embodiments, the drive wheel can be configured to contact thefirst planar side and can be configured to translate the carriageassembly along the rail. A first roller set of the at least two rollersets can be configured to contact the second planar side. A secondroller set of the at least two roller sets can be configured to contactthe third planar side.

In yet other embodiments, the solar panel can be further mounted to asecond rail. The rail and the second rail can be in a planesubstantially parallel to a solar panel. The second rail can includethree planar sides arranged to form at least a third acute angle and afourth acute angle.

In some embodiments, the array can include a trailing carriage assemblyslidably attached to the brush assembly. The trailing carriage caninclude at least three roller sets. The at least three roller setsinclude at least one drive wheel.

In other embodiments, the rotational axis can be nonperpendicular to therail when the photovoltaic array is in an operational configuration.

In yet other embodiments, the array can include a housing for containinga brush assembly. The brush assembly can include at least one rotatablebrush having a rotational axis. The brush assembly can be pivotallyattached to a carriage assembly.

In some embodiments, the array can include a mounting frame configuredto maintain the solar panel in relation to the rail. The mounting framecan include a c-shape cross section and a material for securing thesolar panel. The material can be a polymer, an elastomer, an adhesive,and/or a resin.

In an aspect, a track system can include a channel and a carriage. Thechannel can include a first planar side and a second planar side. Thefirst and second planar sides can be arranged at an acute angle. Thecarriage assembly can include a drive wheel and at least two rollers.The drive wheel can be in contact with the first planar side and can beconfigured to translate the carriage assembly along the channel. Atleast one of the at least two rollers can be in contact with the secondplanar side.

In some embodiments, the carriage assembly can further include a pivot.In other embodiments, the track system can include a means for dustabatement. The means for dust abatement can include a flexible hoodand/or bristles, for instance, along the top of the channel. The meanscan include egress apertures along the bottom and/or sides of thechannel. Additionally, a skirt around the pivot and sliding members canbe utilized to prevent dust and debris from falling into the channel.Further, the assembly components can be disposed in a housing to sealthem from dust and dirt.

In other embodiments, the system can include a brush assembly. The brushassembly can include one or more rotatable brushes, each having arotational axis. The pivot can be configured to pivot the brushassembly.

In yet other embodiments, the system can include a panel. The panel canbe a photovoltaic solar panel, a window, and/or a mirror. The panel canbe mounted to the channel. The top of the channel can be substantiallyflush with the panel. The pivot can be configured to allow pivoting therotational axis in a plane parallel to the panel. The carriage assemblycan be configured to translate the brush assembly in a direction that isnonperpendicular to the rotational axis.

In another aspect, a method of conveying can include the steps ofproviding a channel, providing a carriage assembly, and translating thecarriage assembly along the channel. The channel can include a firstplanar side, a second planar side, and an open face. The first andsecond planar sides can be arranged at an acute angle. The carriageassembly can include a drive wheel and at least two rollers. The drivewheel can be in contact with the first planar side. At least one of theat least two rollers can be in contact with the second planar side.

In some embodiments, the carriage assembly can further include a pivot.The method can further include abating dust ingress into the channel.

In other embodiments, the method can include providing a brush assemblyand pivoting the brush assembly. The brush assembly can include one ormore rotatable brushes each having a rotational axis.

In yet other embodiments, the open face of the channel can besubstantially flush with a panel. The method can further includepivoting the rotational axis in a plane parallel to the panel, andtranslating the brush assembly in a direction that is nonperpendicularto the rotational axis.

In other embodiments, the method can include providing a brush assemblyand pivoting the brush assembly. The brush assembly can include one ormore rotatable brushes each having a rotational axis.

In other embodiments, the cleaning system may include a brush assemblyfor cleaning the solar panels. The brush assembly may include a brushhaving one or more bristles extending outwardly from a core. A shaft mayextend through the core of the brush. The shaft may be a telescopingshaft, which is configured to retract and expand to create an elongatedbrush assembly.

In other embodiments, the track may include a rail comprising a firstplanar side, a second planar side, and a third planar side, wherein thefirst, second, and third planar sides are arranged to form at least twoacute angles. An assembly may include a drive wheel and at least tworollers, wherein the drive wheel is configured to contact the secondplanar side and is configured to translate the assembly along the rail.A bracket may engage an underside of the rail. The rail may beconfigured to snap on to the bracket, and a first roller of the at leasttwo rollers is configured to contact the first planar side, and a secondroller of the at least two rollers is configured to contact the thirdplanar side and hold the assembly on the rail.

In other embodiments, a carriage assembly may include a bracket having afirst side, a second side, and a third side. A shaft may extend betweenthe second side and third side, parallel to the first side of thebracket. The shaft may include a drive roller and a drive motor. A pairof rollers may be attached to the second and third ends of the bracket.The pair of rollers may be configured to attach the carriage assembly tothe rail, while the drive roller may be configured to translate thecarriage assembly along the rail. The rail may be any suitable shape orsize, and may include generally triangular shaped ends or may begenerally U-shaped.

In other embodiments, the rail may be formed from a first side, a secondside, and a third side. The first side, second side, and third side mayform a generally triangular shape having an open cross-section and maydefine two acute angles. An acute angle may be formed between the firstside and the second side, ranging between 30 and 85 degrees. An acuteangle may be formed between the second side and the third side rangingbetween 30 and 85 degrees. The rail may also include a bottom member andan angled member, such that it the third side, bottom member and angledmember form a triangle.

In other embodiments, a cleaning apparatus may have a brush assemblyincluding at least one rotatable brush having a rotational axis. The atleast one rotatable brush may include a core defining a plurality ofsockets. One or more brush bristles may extend from each of theplurality of sockets. The one or more brush bristles may be removablyattached to the plurality of sockets. The cleaning apparatus may alsoinclude a drive configured to translate the brush assembly parallel to atrack.

In other embodiments, a brush assembly may include at least onerotatable brush having a rotational axis. The at least one rotatablebrush may include a core and a plurality of sets of bristles extendingoutwardly from the core. The brush assembly may also include arotational cover surrounding at least a portion of the brush assembly.The rotational cover may rotate around the brush assembly based on thedirection of the rotation of the brush assembly. An area of highpressure may be formed between a first set of bristles, which are in aflexed position and a second set of bristles in an un-flexed position.An area of atmospheric pressure may be formed between two sets ofbristles both in an un-flexed position. An area of low pressure may beformed between the first set of bristles and the second set of bristlesas the first set of bristles moves from a flexed to an un-flexedposition.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are further described in the detailed description whichfollows, in reference to the noted plurality of drawings by way ofnon-limiting examples of certain embodiments of the present invention,in which like numerals represent like elements throughout the severalviews of the drawings, and wherein:

FIG. 1 depicts an exemplary system in an operational position.

FIGS. 2A-2C depict an exemplary system in initial, intermediate, andoperational configurations.

FIGS. 3A and 3B depict an exemplary carriage assembly.

FIG. 4 depicts an exemplary track and cleaning system.

FIG. 5 depicts an exemplary cross section of a rail.

FIGS. 6A-6C depict exemplary configurations of rail cross sections.

FIG. 7 depicts two views of an exemplary track.

FIGS. 8A and 8B depict cross sections of exemplary rails.

FIG. 9 depicts an exemplary cross section of an external rail track.

FIG. 10 depicts an exemplary cross section of an internal rail track.

FIG. 11 depicts an exemplary embodiment of a photovoltaic array system.

FIG. 12 depicts an exemplary embodiment of a photovoltaic array system.

FIG. 13 depicts an exemplary embodiment of a photovoltaic array system.

FIG. 14 depicts an exemplary implementation of a photovoltaic arraysystem.

FIG. 15 depicts a photovoltaic array with a central track system.

FIG. 16 depicts a photovoltaic array during operation of the system.

FIG. 17 depicts a photovoltaic array with an off-center track.

FIG. 18 depicts a photovoltaic array during operation of the system.

FIG. 19 depicts an overhead view and a cross sectional view of aphotovoltaic array during operation of the system.

FIGS. 20A-20E depict an exemplary embodiment of a brush assembly.

FIGS. 21A-21E depict an exemplary embodiment of a rail.

FIGS. 22A and 22B depict exemplary configurations of a carriage assemblyand rail.

FIG. 23 depicts a cross section of an exemplary rail.

FIGS. 24A-24D depict an exemplary embodiment of a rotatable brush.

FIGS. 25A and 25B depict an exemplary embodiment of a brush assembly.

DETAILED DESCRIPTION

Exemplary embodiments described, shown, and/or disclosed herein are notintended to limit the claims, but rather, are intended to instruct oneof ordinary skill in the art as to various aspects of the invention.Other embodiments can be practiced and/or implemented without departingfrom the scope and spirit of the claimed invention. As an example, thedescription below discusses panels primarily with respect tophotovoltaic solar panels. Nonetheless, the term panel can mean awindow, such as a skylight, a mirror, or any plane for which thecleaning system can be utilized.

Applicant hereby incorporates by reference in its entirety U.S.application Ser. No. 13/567,205, filed by Inventor Georg Eitelhuber onAug. 6, 2012. The application was published as US 2013/0037051 A1 onFeb. 14, 2013. The language and embodiments of the application will notbe repeated herein for the purpose of brevity.

An exemplary embodiment is shown schematically in FIG. 1. The track andcleaning system (100) can have a brush assembly (102) with at least onerotatable brush (103) having a rotational axis. A drive can beconfigured to translate the brush assembly parallel to the rail (101). Acarriage assembly (104) for translating the brush assembly can have apivot, which can be configured to allow pivoting of the rotational axisin a plane parallel to the rails and the rotational axis, which is alsoparallel to panel (106). The pivoting action can further be aided by atrailing assembly (105), which can have another pivot that is slidablyattached to the brush assembly. Directional arrow shows the direction oftravel of the brush and carriage assemblies. The angle, θ, between thedirection of travel and the rotational axis of the brushes can be lessthan ninety degrees when the duster is operating.

FIGS. 2A-2C show a cleaning system in an initial configuration, as wellas two operational configurations. As the carriage assembly (204) isdriven across the panel, the pivots in the carriage (204) and trailing(205) assemblies can allow the longitudinal axis of the brushes torotate parallel to the panel. Initially, the brushes can overhang thetrailing assembly. This distance of overhang can decrease as the brushesrotate into an operating position, as shown in FIGS. 2B and 2C.

An advantageous aspect of the system is the way the device can slide upinto an angled position that can allow the top end to lead. This canallow dust and debris to fall forward and away from the brush-panelinterface. The unique roller support on the bottom of the brush assemblycan allow the system to be supported by a cart, always directly over therail.

Leading the top edge of the brush assembly can dramatically increaseeffectiveness of the cleaning in several ways. The dust at the top neednot be re-brushed many times on the way down after being dislodged, ascan happen if the brush is constrained vertically.

Further, the bristle pattern on the brushes can be straight instead ofspiral. This can facilitate flicking the dust and debris from thesurface, rather than grinding them across the panel surface by lateralrelative velocity of a bristle spiral. Yet because of thenonperpendicular angle, with respect to the direction of travel, dustand debris can still be directed towards the bottom edge more rapidly.

In an embodiment, the solar panel cleaning system can incorporate one ormore support assemblies to support the brushes. The system can also haveone or more motors to operate the rotatable brushes and/or a drivewheel. The rotatable brushes can move across a panel in a direction, forexample as shown by the directional arrows in FIGS. 1-4, and/or in theopposite direction. Additionally, the rotatable brushes can pivot to acertain degree across the surface.

When in a run position, i.e. an operational position, the angle θbetween the direction of travel, defined by the direction of the track,and the rotational axis, defined by the longitudinal axis of one or moreof the brushes, can be between zero and 180 degrees. When the brushesare in rest position, the rotational axis can be perpendicular to therails. Further, the rotatable brushes can be rotated counter-clockwiseand/or clockwise from a rest position to reach an operating position.

The embodiment of FIG. 2C shows an operating configuration where theangle has been defined by the length of the brush assembly. Once thesliding member reaches the end of the brush assembly, the trailingassembly can be pulled by the driven carriage assembly at a definedangle. The embodiment of FIG. 2B shows an operating configuration inwhich the brush assembly is allowed to pivot until an equilibrium angleis achieved. The mechanical advantages in the embodiments are manifold.For example, the tracks can have very large tolerances for lateraldistance apart, and the brush can simply find its own angle comfortably.For straight brushes, conversely, such changes in the lateral anglewould result in the system pulling itself apart. Exemplary operatingangles can include 30 to 80 degrees, 40 to 75 degrees, 50 to 70 degrees,55 to 65 degrees, and/or less than 60 degrees.

FIGS. 3A and 3B are an exploded view and a substantially assembleddepiction of the carriage assembly (300). The carriage can have one ormore drive wheels. In the exemplary embodiment of FIG. 3, drive wheel(301) can be attached to motor (303) by means of a coupling (304).Rollers (302) can form a triangular shape when assembled so as to holdtight to a rail with a triangular cross section. The term roller hereincan mean wheel, caster, bearing, roller bearing, and/or other elements.The carriage can further have a pivot (305) mounted to a pivot plate(306) or be otherwise mounted.

The triangular shape of the rollers is shown in the exemplary cleaningsystem (400) of FIG. 4. As can be seen, carriage assembly (402) can beconfigured to hold tight onto rails (401), which have a triangular crosssection. A closer view of the cross section of the rail, includinghollow areas and exemplary internal support structures, can be seen inFIG. 5.

Referring again to FIG. 4, a brush assembly can frame rotatable brushes(403) and be attached to pivots (404). The brush assembly can thereby beattached to the drive wheel, via the carriage assembly, and to thetrailing assembly (408), via a slidable pivot (407). The rotatablebrushes can include a shaft and a sweeping member. The sweeping membercan be made of bristles comprising bristles, such as hair, plastic,and/or metal bristles. Alternatively, the sweeping member can be made offoam and/or sponge.

A brush assembly motor (406) can be used to actuate and/or rotate therotatable brushes about their longitudinal axes. The shaft can becoupled to a drive transmission. The brushes can rotate about their axessuch that the part of the brush in contact with the surface moves in thesame direction as the direction of travel of the brush assembly and/orin the opposite direction. The carriage assembly can be coupled to adrive motor (405). Although not shown in FIG. 4, the trailing assemblycan also be coupled to a drive motor, for example to facilitatereturning the brushes to a perpendicular orientation for storing and/orto facilitate reversing the direction of travel. Alternatively, thebrushes can be configured to return to a perpendicular orientation, withrespect to the track, simply by continuing to rotate the brushes as thedrive motor translates the brush assembly to its starting positionopposite the directional arrow.

In an embodiment, there can be one motor to operate the rotatablebrushes. The brushes can be configured to rotate in the same directionsynchronously or in two different directions through the use of gears.Gearing can be utilized to rotate different brushes of a multi-brushassembly at different speeds. In an embodiment there may be two or moremotors. In such an embodiment, several brushes can be individuallyoperated by different motors.

FIG. 5 shows a rail having a triangular cross section. The shape andinternal support features can be achieved an extrusion process. The railcan be, for example, extruded aluminum. Such is advantageous as the railcan be very stiff and rigid. Moreover, such a rail can have a closedconfiguration and can have good bending moment characteristics.

FIGS. 6A-6C show alternative rail configurations that can beadvantageously fabricated from cold rolling processes. Such materials ascold rolled steel provide many benefits. The rails can be long, withoutseams, and very strong. Cold rolled rails can be very stiff, andordinary cold rolled steel can be utilized inexpensively. Moreover, coldrolled metal can further act as a load bearing member to providestructural support, for example, to an entire photovoltaic array. Thegrey rectangles in FIGS. 6A-6C represent roller positions around therail. An advantage to the triangular cross sections in FIGS. 5 and 6 isthat the number of rollers for maintaining the carriage and/or trailingassemblies on the rails is minimized.

FIG. 7 shows a track system (700) that can include a rail (701). Rollers(702) can be utilized on all three of the planar faces of the rail. Therail can include intermittent supports (703) and fasteners (704), suchas bolts and/or rivets. The intermittent supports can be, though neednot be, attached to a solar panel support or to a solar panel directly.If made for the track alone, and not a load bearing member, intermittentsupports can be used to attach the track to the main support. Thesupports can provide additional stiffness to the cross section of therail by joining the two parts of the rail intermittently.

Although an advantage of the present system is in the minimization ofthe number of rollers and/or roller assemblies required, it may beadvantageous and/or convenient to use rollers on four or five faces of atrack. FIGS. 8A and 8B shows contemplated rail configurations, as wellas various roller positions.

Two alternative embodiments are shown in FIGS. 9 and 10. FIG. 9 shows anexternal rail configuration with a triangular cross section. A drivewheel is represented by the large rectangle on top and two sets ofcomplimentary rollers are represented by the rectangles on either sideof the rail. In FIG. 10, the rollers are internal to the rail. Aninternal rail can be beneficial is it can be more compact than anexternal rail. Moreover, as will be shown, an internal rail can allow abrush system to be disposed close to the plane of a surface by mountingthe rail such that the top of the channel is flush with the surface tobe swept.

FIGS. 11 and 12 show two configurations for positioning a solar panelcleaning system (1100) close to the surface to be cleaned, for example asolar panel surface (1101). A primary roller (1102), i.e. a load-bearingdrive wheel, is positioned on top of a triangular rail (1104). The topsurface of the rail has been disposed in the plane of the solar panelsurface. Complementary rollers (1103) are shown on either side of thetriangular rail. In FIG. 12, the rollers can be more compactlyconfigured within the channel of the rail, dramatically reducing theprofile of the cleaning system. Further, the configuration can allow therail and cleaning system to be disposed very close the surface to becleaned. It can be advantageous to include means for dust abatement,such as a flexible hood or bristles along the top of the channel and/oregress apertures along the bottom of the channel. Additionally, a skirtaround the pivot and sliding members can be utilized to prevent dust anddebris from falling into the channel. Further, the assembly componentscan be disposed in a housing to seal them from dust and dirt.

The system can further include a self-cleaning system configured toautomatically clean the one or more rotatable brushes. The system can beintegrated with a housing for the brushes or merely attached to an edgeof a panel array. A self-cleaning member can include a stiff brush, arow of rake-like tines, a bar, or other effective elements against whichthe rotating brushes can pass while rotating and thereby eliminateexcess dust and debris buildup.

In FIG. 13, similar to FIG. 12, the rollers (1302) can be disposedwithin a channel. The internal rail can be adhered to the solar panels(1301), for example with resin (1303). FIG. 14 additionally shows apivot arm (1404) for attaching to a brush assembly. Rubber strips (1406)with circular cross sections can be attached inside support framemembers (1405) having a C-shaped cross section. The members can be usedto mount the solar panels (1401). The support frame can be bolted to amain array. The support frame can be part of the main array, for exampleas an integral part of an extrusion. As shown in FIG. 14, a panel can beinserted straight (where there is clearance), and then can be let downto an angle of tilt. This can crush the rubber strips, and can therebycause a locking force on the panels. The other end of the panel can beheld down either by a resin stick, by small clamp, and/or by anadhesive. Conversely, the rubber bits can be attached to the panelsthemselves for substantially the same effect.

FIGS. 15-19 show various embodiments of a photovoltaic array. In FIG.15, solar panels (1501) can be mounted to support structures (1503) andtrack (1502). The track can be an internal rail, such as a channel, oran external rail. As shown in FIG. 16, the cleaning system (1602) can becentrally mounted to a pivot connected to a carriage assembly whichutilizes only a central track. Alternatively, trailing roller assembliescan be incorporated along the top, bottom, or top and bottom edges ofthe array of solar panels (1601), similar to embodiments shown in FIGS.1-4.

Referring to FIGS. 17 and 18, the array of solar panels (1701) caninclude a track (1702) that is off center. Here also, the track can bean internal rail, such as a channel, or an external rail. The carriageand pivot (1804) can be utilized alone or in combination with otherroller assemblies to translate and pivot the cleaning system (1803).

For a centrally located track, it can be advantageous to incorporate atrailing assembly with its own drive or motor, or to incorporate arolling resistance to facilitate pivoting. A motor can be integratedwith the pivot to produce a power-actuated pivot.

In FIG. 19, solar panels (1901) can be supported by and mounted to rails(1905). Brush assembly (1903) can be translated and operated by carriageassembly (1902). The translation, orientation, and support of the brushcan further be facilitated by a trailing roller assembly (1904). Asshown above, the carriage and the trailing assembly can havesubstantially similar roller configurations.

The cleaning system can further include a monitoring device to determinewhether a cleaning is required. The device can include a meter of theoutput of the solar panels. Alternatively, the device can include sensorsystem for measuring the efficiency and/or effectiveness of thephotovoltaic elements.

The monitoring device can be in communication with a control device. Thecontrol device can be configured to activate the cleaning system. Thecontrol device can be configured to send a signal indicating the statusand/or the need for cleaning a panel. Additionally, the control devicecan be configured to send a signal indicating a fault or error in thearray system, including in the cleaning system.

Referring to FIG. 20A, a cleaning system (2000) for cleaning solarpanels (2010) is depicted. The cleaning system (2000) may include abrush assembly (2001) for cleaning the solar panels (2010). The brushassembly (2001) may include a brush (2003), as depicted in FIG. 20B. Thebrush (2003) may include one or more bristles (2004) extending outwardlyfrom the core (2008). A shaft (2005), as illustrated in FIG. 20C, mayextend through the core (2008) of the brush (2003). The shaft (2005) maybe a telescoping shaft, which is configured to retract and expand tocreate an elongated brush (2003).

The shaft (2005) may be connected to a slider-bearing hub assembly(2006), as illustrated in FIGS. 20D and 20E, that allows the shaft(2005) to expand and retract. The slider-bearing hub assembly (2006) mayinclude any necessary components to allow the shaft (2005) to expand andretract. For example, the slider-bearing hub assembly (2006) may includeone or more washers, nuts, couplings, retainers, screws, bolts, keys,seals, bushings, etc.

Referring back to FIG. 20A, the brush assembly (2001) may include acover (2002) that surrounds at least a portion of the brush (2003). Inat least one embodiment, the cover (2002) may surround at least 180degrees of the brush (2003). In other embodiments, the cover (2002) maysurround more than 180 degrees of the brush (2003) or may surround lessthan 180 degrees of the brush (2003). For example, the cover (2002) maysurround approximately 270 degrees or the majority of the brush (2003).The cover (2002) may be any suitable shape or material. In embodiments,the cover in generally arc-shaped.

The telescoping shaft (2005), allows the brush assembly (2001) to beattached at either end to a carriage or trailing assembly (2007), whichin turn may be attached to and configured to move along a rail. Thetelescoping shaft (2005) may be configured to expand and retract as theangle or the direction of movement of the brush assembly (2001) changes.Alternatively, the telescoping shaft (2005) may be configured to expandand retract to extend between different rail widths, while the angle ofthe brush assembly (2001) remains constant.

Referring to FIG. 21A, triangular rail (2201) having a generallytriangular shape and an open cross-section is depicted. The triangularrail (2201) may snap on to a bracket (2202), as shown in FIGS. 20B-20D.The triangular rail (2201) may eliminate the need for fasteners to holdthe rail (2201) to the bracket (2202). The shape of the triangular rail(2201) may have an advantage of simplifying the design and reducing themanufacturing cost of a track and cleaning system for solar panels. Acarriage or trailing assembly (2204) may be attached to the rail (2201).The carriage or trailing assembly (2204) may include a plurality ofrollers or roller sets (2203). In embodiments, the carriage or trailingassembly (2204) includes three rollers (2203), a first roller (2203) maycontact a first side of the triangular rail (2201), a second roller(2203) may contact a second or top side of the triangular rail (2201),and a third roller (2203) may contact a third side of the triangularrail (2201).

The first, second, and third side of the triangular rail (2201) may bepositioned at any angle. For example, the first and third sides of thetriangular rail (2201) may be at an angle, and the second side may be ina horizontal plane. In at least one embodiment, the first, second, andthird sides of the triangular rail (2201) are arranged to form two acuteangles, such the first and third sides extend toward each other. Eachside of the triangular rail (2201) may be planar surfaces. One or morerollers (2203) may be configured to hold the assembly (2204) in place.For example, the first and third rollers (2203) may hold the assembly(2204) on the rail (2201), while the second roller (2203) may be a driveroller that is configured to translate the assembly (2204) along therail (2201). The open cross-section of the triangular rail (2201) mayallow the bracket (2202) to fit within the rail (2201). For example, atop portion of the bracket (2202) may be configured to contact a bottomsurface of the second side of the rail (2201), while the first and thirdsides of the rail (2201) are each configured to contact a side portionof the bracket (2202).

The rail (2201) may be made of any suitable material, including coldrolled steel and aluminum extrusion. In embodiments, the rail (2201) maybe placed at any angle. For example, the rail (2201) can be positionedsuch that one side of the triangle is in a horizontal plane.Alternatively, the rail (2201) can be inverted or at any angle. Thebracket (2202) may be any suitable shape. In at least one embodiment,the end of the bracket (2202) is U-shaped.

Referring to FIG. 22A, a carriage assembly (2100) and a rail (2120) areshown. The rail (2120) may be any suitable shape or size. Inembodiments, the rail (2120) includes a first side (2121), a second side(2122) and a third side (2123). The second side (2122) and third side(2123) may extend from the first side (2121), each at an angle. Inembodiments, the first side (2121), second side (2122), and third side(2123) form two acute angles. The acute angles may be any suitable angleless than 90 degrees. In embodiments, the second side (2122) and thirdside (2123) each form a generally triangular shape at one end of thefirst side (2121). Alternatively, the rail (2120) may be generallyU-shaped.

The carriage assembly (2100) may include a bracket (2101) having a firstside (2102) and a second side (2103). The bracket (2101) may include ashaft (2104) and a drive roller (2105) attached to the shaft (2104). Theshaft (2104) may extend between the second side (2102) and third side(2103) of the bracket (2101) and may be parallel to the first side(2101). The shaft (2104) may extend through one or more of the secondside (2102) or the third side (2103) of the bracket (2101). Inembodiments, a drive motor is attached to the shaft (2104). The drivemotor may be attached to the shaft (2104) in any suitable manner,including via a bracket and a coupling. The drive roller (2105) may beconfigured to move the carriage assembly (2100) across a surface, suchas the first surface (2121) of the rail (2120).

The carriage assembly (2101) may include a plurality of rollers (2106,2107). The rollers (2106, 2107) may be attached to the second end (2102)and third end (2103) of the bracket (2101). The rollers (2106, 2107) maybe attached to the bracket (2101) by any suitable means. The rollers(2106, 2107) may be configured to keep the carriage assembly (2100) tothe rail (2120).

The carriage assembly (2100) may be attached to a rail (2120) that ispositioned in any direction. For example, the rail (2120) may behorizontal, vertical, or at any angle. In at least one embodiment, therail (2120) can be an edge of one or more solar panels. Alternatively,the rail can be a support member for a row of solar panels. The carriageassembly can be made of any suitable material, such as an extrusion orcold-rolled array structure.

Referring to FIG. 23, the rail (2301) may have a generally triangularshape and an open cross-section. The rail (2301) may be formed from aplurality of sides. For example, the rail (2301) may be formed from afirst side (2302), a second side (2303), and a third side (2304). Thefirst side (2302), second side (2303), and third side (2304) may form agenerally triangular shape having an open cross-section and may definetwo acute angles. For example, an acute angle may be formed between thefirst side (2302) and the second side (2303). The acute angle may be anysuitable angle. For example, the acute angle may range between 30 and 85degrees. In at least one embodiment, the acute angle formed between thefirst side (2302) and the second side (2303) is approximately 70degrees.

An acute angle may be formed between the second side (2303) and thethird side (2304). The acute angle may be any suitable angle. Forexample, the acute angle may range between 30 and 85 degrees. In atleast one embodiment, the acute angle formed between the second side(2303) and the third side (2304) is approximately 60 degrees. The rail(2301) may also include a bottom member (2305) and an angled member(2306). The bottom member (2305) may be attached to the third side(2304). The bottom member (2305) may be parallel to the second side(2303). The angled member (2306) may be attached to the bottom member(2305) and the third side (2303), such that the third side (2303),bottom member (2305) and angled member (2306) form a triangle. Theangled member may be positioned at any suitable angle. For example,approximately a 30 degree angle may be formed by the angled member(2306) and the bottom member (2305). Alternatively, the angle may begreater or less than 30 degrees.

The first side (2302), second side (2303), third side (2304), bottommember (2305), and angled member (2306) may all be planar surfaces. Therail (2301) may be made from any suitable material such as cold rolledsteel or aluminum extrusion. The first side (2302), second side (2303),third side (2304), bottom member (2005), and angled member (2306) mayhave any suitable dimensions, including the dimensions depicted in FIG.23.

Referring to FIG. 24A, a rotatable brush (2400) in accordance withaspects of this invention is shown. The rotatable brush (2400) mayinclude a core (2401), as shown in FIG. 24B, and bristles (2410) asshown in FIG. 24C. Referring back to FIG. 2B, the core (2401) mayinclude a plurality of sockets (2402) for receiving the bristles (2410).Any number of sockets (2402) may be included on the core (2401). Each ofthe sockets (2402) may receive any number of bristles (2410). Forexample, each socket (2402) may receive a single bristle (2410) or aplurality of bristles (2410). In at least one embodiment, each socket(2402) is configured to receive a bristle assembly, which comprises aplurality of bristles (2410) joined together. The core (2402) may bemade from any suitable material. In at least one embodiment, the core(2401) is made from a single aluminum extrusion.

The sockets (2402) may extend into the core (2401), as illustrated inFIG. 24B. Alternatively, the sockets (2402) may extend outwardly fromthe core (2401), as illustrated in FIGS. 20C and 20D. The sockets mayinclude a first socket side (2403) and second socket side (2404), whichare configured to hold the bristles (2410) in the socket (2402). Thefirst socket side (2403) and the second socket side (2004) may be angledtoward each other to hold the bristles (2410) between them. In at leastone embodiment, the bristles (2410) may be removably attached to thesockets (2402), such that they can be replaced.

Referring to FIG. 25A, a rotatable brush assembly (2500) in accordancewith aspects of this invention is shown. The rotatable brush assembly(2500) may include a core (2501) and bristles (2502) extending outwardlyfrom the core (2501). The bristles (2502) may surround the core (2501),such that there is spacing between each of the bristles, or may bearranged in clusters or sets, having a plurality of clusters or sets ofbristles (2502) around the core (2501). The rotatable brush assembly(2500) may include a rotatable axis (2503) and a cover (2504). The cover(2504) may be configured to extend over at least a portion of the brushassembly (2500). In at least one embodiment, the cover (2500) isconfigured to surround approximately 180 degrees of the brush assembly(2500). Alternatively, the cover (2500) may be configured to surroundless than 180 degrees of the brush assembly (2500) or more than 180degrees of the brush assembly (2500). The cover (2504) may be anysuitable shape or material. For example, the cover (2504) may begenerally arc-shaped. The cover (2504) may be any suitable spacing fromthe bristles (2502). For example, the cover (2504) may be spaced fromthe brush assembly (2500) such that the ends of the bristles (2502) justtouch an inner surface of the cover (2504). The cover (2504) may includea plurality of static bristles (2505). The plurality of static bristles(2505) may extend from the edges of the cover (2504) and be configuredto contact the surface being cleaned.

During operation of the brush assembly (2500), the bristles (2502)contact the surface that is being cleaned, such as a solar panel. Whenthe bristles (2502) are un-flexed and the ends just touch the cover(2504), an area of atmospheric pressure (2510) occurs between sets ofbristles (2502) as illustrated in FIG. 25B. When the bristles (2502)contact a surface, the bristles (2502) flex, reducing the amount ofspace between the flexed set of bristles (2502) the adjacent set ofbristles (2502), which may cause an area of high pressure (2511) orcompressed air between two adjacent sets of bristles (2002). The staticbristles (2505) of the cover (2504) may help maintain the area of highpressure (2511) between adjacent bristles (2502) by trapping the airbetween the two sets of adjacent bristles (2502) rather than letting theair escape. When the bristles (2502) move from the flexed to un-flexedposition, after contacting the surface, the high pressure region (2511)is transformed into a low pressure region (2512). The change betweenhigh pressure (2511) and low pressure regions (2512) causes a boost ofcompressed air, which increases the velocity of the dust and/orparticulates being swept off the surface, which is designated by thedirection “a” in FIG. 25B. The change between high pressure (2511) andlow pressure regions (2512) may remove the dust and/or particulates fromthe surface at a faster rate without adding friction to the surface. Thecover (2504) may rotate around the brush assembly (2500) when the brushassembly is moving, such that the static bristles (2505) are in contactwith the surface being cleaned. The change from high pressure (2511) tolow pressure (2512) as the flexed bristles un-flex may also reduce theamount of particulates that remain on the bristles (2502).

Details of one or more embodiments are set forth in the accompanyingdrawings and description. Other features, objects, and advantages willbe apparent from the description, drawings, and claims. Although anumber of embodiments of the invention have been described, it will beunderstood that various modifications may be made without departing fromthe spirit and scope of the invention. It should also be understood thatthe appended drawings are not necessarily to scale, presenting asomewhat simplified representation of various features and basicprinciples of the invention.

What is claimed is:
 1. A cleaning apparatus, comprising: a brushassembly comprising at least one rotatable brush having a rotationalaxis, wherein the brush assembly is attached to a carriage assembly,wherein the carriage assembly is configured to translate the brushassembly along a rail, and wherein the brush assembly includes atelescoping shaft which is configured to expand and retract to brushassembly.
 2. The cleaning apparatus of claim 1, wherein angle of thebrush assembly relative to a solar panel changes when the telescopingshaft expands.
 3. The cleaning apparatus of claim 1, wherein thetelescoping shaft extends through a core of the brush assembly.
 4. Atrack system, comprising: a rail comprising a first planar side, asecond planar side, and a third planar side, wherein the first, second,and third planar sides are arranged to form at least two acute angles;an assembly comprising a drive wheel and at least two rollers, whereinthe drive wheel is configured to contact the second planar side and isconfigured to translate the assembly along the rail; a bracketconfigured to engage an underside of the rail; and wherein the rail isconfigured to snap on to the bracket, and wherein a first roller of theat least two rollers is configured to contact the first planar side, anda second roller of the at least two rollers is configured to contact thethird planar side and hold the assembly on the rail.
 5. The track systemof claim 4, wherein an end of the bracket is U-shaped.
 6. The tracksystem of claim 4, wherein the rail defines an open cross-section.
 7. Atrack system, comprising: a carriage assembly having a bracket, thebracket defining a first side, a second side, and a third side, a shaftextending between the second side and the first side and parallel to thefirst side, a drive roller positioned on the shaft, and a pair ofrollers; and a rail having a first side, a second side, and a thirdside, wherein the drive roller is configured to engage the first side ofthe rail and translate the carriage assembly along the rail, wherein afirst roller of the pair of rollers is configured to engage the secondside of the rail and a second roller of the pair of rollers isconfigured to engage the third side of the rail, and wherein the firstand second roller are configured to attach the carriage assembly to therail.
 8. A track system, comprising: a rail comprising a first planarside, a second planar side, and a third planar side, wherein the first,second, and third planar sides are arranged to form at least two acuteangles ranging between 50 degrees and 80 degrees; a carriage assemblycomprising a drive wheel and at least two roller sets, wherein the drivewheel is configured to contact the second planar side and is configuredto translate the carriage assembly along the rail; and wherein a firstroller set of the at least two roller sets is configured to contact thefirst planar side, and a second roller set of the at least two rollersets is configured to contact the third planar side.
 9. The track systemof claim 8, wherein the first planar side and the second planar sideform an acute angle of approximately 70 degrees.
 10. The track system ofclaim 8, wherein the second planar side and the third planar side forman acute angle of approximately 60 degrees.
 11. A cleaning apparatus,comprising: a brush assembly comprising at least one rotatable brushhaving a rotational axis, the at least one rotatable brush including acore defining a plurality of sockets, wherein one or more brush bristlesextend from each of the plurality of sockets; and a drive configured totranslate the brush assembly parallel to a track.
 12. The cleaningapparatus of claim 11, wherein the one or more brush bristles areremovably attached to each of the one or more sockets.
 13. The cleaningapparatus of claim 11, wherein the of sockets extend outwardly from thecore.
 14. The cleaning apparatus of claim 11, wherein the plurality ofsockets extends inwardly toward the core.
 15. A cleaning apparatus,comprising: a brush assembly comprising at least one rotatable brushhaving a rotational axis, the at least one rotatable brush including acore and a plurality of sets of bristles extending outwardly from thecore, the plurality of sets of bristles including at least a first setof bristles and a second set of bristles; and a rotational coversurrounding at least a portion of the brush assembly, the rotationalcover including one or more static bristles extending from edges of therotational cover, wherein the rotational cover rotates around the brushassembly based on the direction of the rotation of the brush assembly,and wherein an area of high pressure is formed between a first set ofthe first set of bristles when the first set of bristles is in a flexedposition, a second set of bristles adjacent the first set of bristles,and one or more static bristles.
 16. The cleaning apparatus of claim 15,wherein the rotational cover surrounds at least 180 degrees of the brushassembly.
 17. The track system of claim 1, wherein the rotational coversurrounds approximately 180 degrees of the brush assembly.
 18. The tracksystem of claim 15, wherein an area of low pressure is formed betweenthe first set of bristles and the second set of bristles when the firstset of bristles moves between the flexed position and an un-flexedposition.